Switchblade knife



FIG. 1 is a rear elevation view of a switchblade knife showing the new design;

FIG. 2 is a front elevation view thereof

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a right side elevation view thereof; and,

FIG. 7 is a perspective view thereof.

The broken lines depict portions of the switchblade knife in which the design is embodied that are not considered part of the claimed design. 

CLAIM The ornamental design for a switchblade knife, as shown and described. 